Control system for amphibious hydraulic excavator

ABSTRACT

An amphibious hydraulic excavator, comprising an amphibious crawling truck, a revolving platform rotatable on said crawling truck, a shovel assembly mounted on said revolving platform and composed of a boom, arm and bucket, hydraulic actuator means for driving said mentioned parts of the excavator, and a prime mover installed on said revolving platform, characterized in that said mentioned parts are fabricated water-tight while said prime mover being provided with a schnorkel or breathing mast for use of air suction and exhaust, thereby enabling the excavator to be operated under water.

United States Patent Hirano et al. 1 Jul 1, 1975 CONTROL SYSTEM FORAMPHIBIOUS 3.086.305 4/1963 WBSl 37/71 x HYDRAULIC EXCAVATOR 3.568.4543/l97l ltami 37/56 X 3,583,585 6/l97l Joyce i 1 1 1 37/103 X [75]Inventors: Kinichi Hirano, Tsuchiura; Yoshiaki 3 59 3 7 1971 v Geuns 375 Metsugi, Tokyo. both of Japan 3.631362 1/1972 Fuzzell w i (ill/DIG. 2

. 3.672.725 6/l972 Johnson 1 1 1 i 1 v 37/DlGi 8 [731 Assgnw cmstrucm"Machmery 3.683.521 8/]972 Sloan Cl 111. i i 1 1 1 a M 37/56 -i Japan3.706,]42 12/1972 Brunner 37/56 [22] Filed: Dec. 26, I972 PrimaryExaminer-Clifford D. Crowder [2.] Appl' 318700 Attorney. Agent, orFirm-Craig and Antonelli [30] Foreign Application Priority Data 57]ABSTRACT Dec. 27, l97l Japan 46405322 v An amph1b1ous hydraullcexcavator. comprlsing an {52] U05 CL M 37/56; 37/71, 37/DIG amphibiouscrawling truck. a revolving platform rotatolDlG 9H4 91/459. able on saidcrawling truck, a shovel assembly 34/158 ZI'MDIO mounted on saidrevolving platform and composed of 511 1m. (:1. E02f 3/32; EOZf 5/28 andbuckeh hydraulic actual means Field of Search 37/56. H. DIG. 8, DIG. l;172/2, 3; 214/DlG. 2, 776, 138 R; 9l/459, 461, 414, 411; 60/DIG. 2;180/82 R, 98

driving said mentioned parts of the excavator, and a prime moverinstalled on said revolving platform. characterized in that saidmentioned parts are fabricated water-tight while said prime mover beingprovided with a schnorkel or breathing mast for use of air suction andexhaust, thereby enabling the excavator to be operated under water.

l Claim, 2 Drawing Figures SHEET FIG. 2

lllllll OIL RESERVIOR CONTROL SYSTEM FOR AMPHIBIOUS HYDRAULIC EXCAVATORBACKGROUND OF THE INVENTION This invention relates to an amphibioushydraulic excavator, and more particularly to an amphibioushydraulic-driven excavating machine such as dozershovel or power-shovelwhich is capable of operating in water.

When carrying out various operations of excavatingshovelling or loadingof the diggings at the bottom of a river or sea-bed especially of smalldepth of water. it has hitherto been a common practice that by applyingthe cofferdamming method the specific working area of the river-bed orsea-bed is provisionally dried up so as to enable the ordinary hydraulicexcavator to be operated unobjectionably around the dried riverorseabed.

Also, for the working location where the depth of water is comparativelygreater. dredgers and the like have been used to grab and bring up sandand mud excavated from the riveror sea-bed by means of a clamshell orsuch provided on board.

However. in the former method of temporarily damming up a necessaryspace in the river or sea wherein the hydraulic excavator can beoperated. there involves the difficulty that it takes an extended periodof time to settle the bottom of river or sea in a dried condition;

while the latter method using a clamshell-equipped boat being highlyexpensive with respect to necessary equipments.

In consideration of those facts described, it has become an urgentnecessity. in the art of excavating and loading operations around theriverand sea-bed. to provide a novel type of hydraulic excavator whichcan perform its function even in water.

SUMMARY OF THE INVENTION An object of the invention is to obviate theabove described prior art defects by providing an amphibious hydraulicexcavator which can be unobjectionably operated even in water.

Another object of the invention is to provide an amphibious hydraulicexcavator which can be remote radie-controlled.

Still another object is to provide an amphibious hy draulic excavatorwhich makes it possible to practice manual operations by the operatoraboard as well as remote radio-control.

The amphibious hydraulic-driven shovel according to the inventioncomprises: an amphibious crawlermounted truck; hydraulic motors fordriving said truck; a revolving platform mounted rotatably on saidtruck; a further hydraulic motor for rotatingly driving said revolvingplatform; a shovel assembly consisting of a boom. an arm and a bucket,each being actuated by a respective hydraulic cylinder; at prime moverinstalled on said revolving platform; hydraulic pumps to be driven bysaid prime mover for producing necessary pressure fluid; directionalcontrol valves for controlling the flows of the pressure fluid to be fedto and for said hydraulic motors and cylinders. respectively; and meansfor actuating said directional control valves. characterized in that allthe parts of the hydraulic excavator are fabricated water-tight whilesaid prime mover being provided with a schnorkel apparatus or breathingmast for use of air suction and exhaust.

The objects and features of the invention will become more apparent bythe following description of an embodiment taken in conjunction with theaccompanying drawings. wherein:

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a schematic elevation of anamphibious hydraulic excavator of the invention; and

FIG. 2 is a hydraulic circuit diagram showing how the excavator ishydraulically operated according to the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1 and 2.reference numeral I indicates an amphibious crawler-mounted truck; 2indicates a revolving platform mounted on the truck I for turningmovement thereon through a water-tight pintle 3; 4 indicates a boomconnected to the revolving platform 2 and adapted for upward anddownward swingable movement; 5 indicates an arm provided in connectionat the extreme end of said boom 4; 6 indicates a bucket mounted at theextreme end of said arm; 7 and 8 indicate left-and right-side tractionhydraulic motors. respectively; 9 indicates a hydraulic motor fordriving the revolving platform 2; and numerals 10, 11 and 12 indicatehydraulic cylinders for actuating the boom 4, arm 5 and bucket 6,respectively. All of the parts described above are driven or actuated byhydraulic pressure.

Numeral 13 indicates an engine room installed on the revolving platform2. in which room 13 are provided a prime mover l4 and its associatedparts including a radiator etc.. all in a water-tight arrangement. 15indicates a schnorkel or breathing mast extending upwardly from theengine room 13 and it serves as an air intake and exhaust conduit forthe prime mover l4. Numeral 17 shows a radio receiver which is stored ina water-tight container 19 provided at the front portion of therevolving platform 2; and 16 shows its antenna. It is arranged that theantenna 16 receives radio signals sent from a radio transmitter 18actuated by the operator who controls the submerged excavator fromashore. Numerals 20 and 21 show hydraulic fluid pumps. respectively.driven by the prime mover l4, and 22 shows an auxiliary pump whichserves to supply a pilot pressure for two three-valve assemblies. aswill be described hereinafter. 23 indicates a universal joint couplerfor prevention of undesirable twisting or flexture in the lead lines tothe traction fluid motors; and 24 indicates an oil or fluid reservior.

Numeral 25 shows a 3-valve assembly composed of pilot-operateddirectional control valves 25a, 25b and 250 juxtaposed to one another.in which the valve 250 is for a fluid line to the hydraulic motor 9, thevalve 25b for that to the cylinder 11 for actuation of the arm, and thevalve 250 is for that to the left-sided traction fluid motor 7. Another3valve assembly is shown at 26 as composed of pilot-operated directionalcontrol valves 26a. 26b and 26c also arranged in juxtaposition. whichvalves being connected on respective lines to the rightsided tractionfluid motor 8, the cylinder 12 for the bucket and the cylinder I0 forthe boom.

Reference numerals 27 through 32 indicate solenoid valves for use in theoperation of remote radio-control.

and each solenoid valve is specifically fabricated in a water-tightdesign or housed within a water-tight protective container. The solenoidvalves 27 through 32 are in communication, via respective shuttle valves33, with the corresponding directional control valves 25a through 25c inthe assembly 25 and those 26a through 26c in the assembly 26, in thatorder mentioned.

In this arrangement, the solenoid valves 27 through 32 are adapted to beenergized by electric signals sent from the radio receiver 17 throughrespective watertight cables 34 so that pilot pressure fluid from theauxiliary pump 22 be supplied to the directional control valves in the3-valve assemblies 25 and 26. Numerals 35 through 40 indicate manualflow control valves to be used by the operator riding on the excavator,and these manual flow control valves are in connection, through therespective shuttle alves 33, with the directional control valves 250through 25c and 26a through 260 of the 3-valve assemblies 25 and 26, ina corresponding manner.

It is also arranged that the manual flow control valves 35 through 40serve to meter the flow of pilot pressure fluid from the auxiliary pump22 to the directional control valves of the 3-valve assemblies 25 and26, in response to the angular displacement of their respective levers.

In another word, it is possible with this arrangement that thedisplacement of the valve spool to be attained in each directionalcontrol valve in the 3-valve assemblies varies depending on the degreeof angular displacement effected in the operating lever of theassociated manual flow control valve so that flow-metering effect isattainable to the hydraulic actuators hence controlling their workingspeeds in a desired manner.

The invention will now be described of its mode of operation again withreference to the drawings.

First, the mode of operation according to the invention will bedescribed for the applied case in which the hydraulic excavatorpositioned at the bottom of sea or river is remote radio-controlled forthe operation of raising or lowering its boom, for example, from land oraboard,

The radio transmitter 18 sends a triggering signal specified for theoperation of raising the boom 4 to the radio receiver 17, which receiver17 then responds to energize the solenoid valve associated with the boomcylinder so that the pilot pressure fluid from the auxiliary pump 22 isdelivered to the respective shuttle valve 33.

As the pilot pressure fluid from the auxiliary pump 22 is then directedto the directional control valve 26c, the latter valve changes itsposition such that pressure fluid delivered from the hydraulic pump 21is applied upon the working surface of the piston head in the boomcylinder 10. Thus, the piston rod in the boom cylinder 10 extends fromthe cylinder to raise the boom.

When it is desired to lower the boom 4, the similar step will be takenin that a different signal specified for lowering ofthe boom is sent tothe receiver 17 from the transmitter 18; then the solenoid valve 32 isactuated to change its position so that the directional control valve26c is supplied with the pilot pressure fluid from the auxiliary pump 22through the associated shuttle valve 33; the valve 26c changes itsposition to direct the flow of pressure fluid from the pump 21 to theside of the piston rod in the boom cylinder 10; and thus the piston rodyields to lower the boom 4.

As apparent from the foregoing, it will be appreciated that by sendingspecified triggering signals through the radio transmitter and receiver18 and 17, the corresponding directional valves 250 through 25c and 26athrough 26c are actuated to operate their respective hydraulic actuatorssuch as the hydraulic motor 9, arm cylinder 11, traction motors 7 and 8,bucket cylinder 12, and boom cylinder 10, through cooperation of theassociated solenoid valves 27 to 32 and shuttle valves 33, so that theremote radio-controlled operation of all the working elements includingthe boom 4, arm 5, etc can be accomplished in an efiicient manner.

Secondly, the mode of manual operation by the operator riding on thehydraulic excavator will be described by way of referring to actuatingthe boom.

Raising or lowering the boom 4 is attained through the function of themanual flow control valve 40. Namely, when the lever of the manual valve40 is rotated, the directional control valve 260 is suppliedincreasingly with the pilot pressure fluid from the auxiliary pump 22 tochange its position so that the pressure fluid from the hydraulic pump21 is applied upon the piston head in the boom cylinder 10, thusextending the piston rod to raise the boom 4.

When actuating further the lever of the manual valve, the pilot-operateddirectional control valve changes its position, due to the function ofthe shuttle valve, such that the pressure fluid from the pump isdirected to the side of the piston rod in the boom cylinder, thus thepiston rod being yielded to lower the boom.

Therefore, the operator riding on the excavator can carry out thenecessary operations in the same manner as in the ordinary shovel, byactuating the manual control valves 35 through 40.

Also, with this mode of operation by the operator riding on the machine,there is provided an advantage that by adjusting the rotating stroke ofthe lever in each manual flow control valve, the operator can controlthe flow rate of pressure fluid to the corresponding hydraulic actuatorthereby attaining a desired rate of its working speed.

According to the amphibious hydraulic excavator of the invention, it ismade possible to perform various works under water such as river orharbor excavating works including digging up the bottom of river or seaand loading the diggings onto the dump boat, in a remarkably easymanner, by virtue of the improved re' mote radio-controlled operation,Additionally, the invention also makes it possible, again thanks to itsfeatured operation of remote radio-controlling, to perform suchexcavating operations at a working field on land with adverseenvironmental conditions such as an obstructed view, hazard inoperation, presence of noxious gasses, unbearble heat, etc.

Since the hydraulic excavator of the invention can be operated either ina radio-controlled manner or in an ordinary manner by the operatorriding on the machine, there will conveniently be provided free choiceon the operating system well adapted for the working conditions, thusmaking contribution to significantly alleviating the physical fatigue ofthe operator as well as bettering the working conditions.

What is claimed is:

I. An amphibious hydraulic excavator comprising: an amphibious crawlingtruck; hydraulic motors for driving said crawling truck; a revolvingplatform mounted rotatably on said truck; a further hydraulic motor forrotating said revolving platform; a shovel assembly mounted on saidrevolving platform and composed of a boom, an arm and a bucket which areactuated by respective hydraulic cylinders; an engine room mounted onsaid revolving platform; a prime mover installed in said engine room;hydraulic pumps driven by said prime mover for delivering pressurefluid; pilot operated directional control valves for controlling theflows of pressure fluid to and from said hydraulic motors and saidhydraulic cylinders, respectively; a snorkle means extending upwardlyfrom the engine room for serving as an air suction and exhaust conduitfor said prime movers; means for actuating said directional controlvalves, said actuating means being activated by radio signals andincluding a radio receiver for receiving triggering signals; a source ofpilot pressure fluid; fluid lines connecting said source of pilotpressure fluid with the respective directional control valve; solenoidvalves provided on the respective fluid line for actuation in re sponseto the triggering signals received by said receiver so as to control theflows of pilot pressure fluid to said directional control valves,respectively; shuttle valves positioned on the respective fluid linesdownstream of said solenoid valves; by-pass fluid lines connectingbetween said source of pilot pressure fluid and the respective shuttlevalves; and manual control valve means provided on the respectiveby-pass fluid lines for controlling the flows of pilot pressure fluid tosaid directional control valves, said manual control valve means beingprovided for adjusting the flow rate of pilot pressure fluid to saidrespective directional control valve; and wherein every part of saidexcavator is fabricated water-tight whereby said hydraulic excavator canbe operated either in a remote radio-controlled manner or by normalmanual operation.

1. An amphibious hydraulic excavator comprising: an amphibious crawlingtruck; hydraulic motors for driving said crawling truck; a revolvingplatform mounted rotatably on said truck; a further hydraulic motor forrotating said revolving platform; a shovel assembly mounted on saidrevolving platform and composed of a boom, an arm and a bucket which areactuated by respective hydraulic cylinders; an engine room mounted onsaid revolving platform; a prime mover installed in said engine room;hydraulic pumps driven by said prime mover for delivering pressurefluid; pilot operated directional control valves for controlling theflows of pressure fluid to and from said hydraulic motors and saidhydraulic cylinders, respectively; a snorkle means extending upwardlyfrom the engine room for serving as an air suction and exhaust conduitfor said prime movers; means for actuating said directional controlvalves, said actuating means being activated by radio signals andincluding a radio receiver for receiving triggering signals; a source ofpilot pressure fluid; fluid lines connecting said source of pilotpressure fluid with the respective directional control valve; solenoidvalves provided on the respective fluid line for actuation in responseto the triggering signals received by said receiver so as to control theflows of pilot pressure fluid to said directional control valves,respectively; shuttle Valves positioned on the respective fluid linesdownstream of said solenoid valves; by-pass fluid lines connectingbetween said source of pilot pressure fluid and the respective shuttlevalves; and manual control valve means provided on the respectiveby-pass fluid lines for controlling the flows of pilot pressure fluid tosaid directional control valves, said manual control valve means beingprovided for adjusting the flow rate of pilot pressure fluid to saidrespective directional control valve; and wherein every part of saidexcavator is fabricated water-tight whereby said hydraulic excavator canbe operated either in a remote radio-controlled manner or by normalmanual operation.